Abstract
Hypothalamic grafts from embryos, larvae, and adults, of the Pacific Treefrog, Hyla regilla, and the Tiger Salamander, Ambystoma tigrinum, homoplastically transplanted to young larvae previously hypophysectomized at the tailbud stage, evoked melanin dispersion and aggregation of reflecting pigment in host chromatophores. To avoid contamination with adenohypophysial hormones hypothalamic tissue was excised from embryos prior to contact with the adenohypophysial anlage and from “albino” larvae and adults hypophysectomized at least one week previously. Sustained responses by adult brain tissue were limited to grafts from ventral parts of the post optic ventral hypothalamus. Responses by grafts from other areas of the hypothalamus and adjacent regions of the brain disappeared within a few days. Histological examination of positive and negative grafts confirmed their exclusively neural origin but did not reveal the cells responsible for the chromatophorotropic activity.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
